So, even if we discount any possibility of qualitative differences between the various ethnicities that have now replaced the relatively homogenous white population, we should expect a) a move towards increasingly authoritarian, winner-takes-all, short term-oriented government, and b) an eventual breakup into two or three political entities.

The obvious one, of course, is the split between Hispanic America in the southwest and the rest of the country. However, as we've seen with the Euro debacle, once it becomes obvious that one split is on the cards, others will become seen to be increasingly viable. And once the Hispanic portion of the country exercises its legitimate right to self-determination and goes its own way, presumably before 2033, it seems readily apparent that White America will at long last separate into its "liberal" and "conservative" halves when conservative America finally realizes that the country, to say nothing of the nation, was literally unable to survive the self-destructive tendencies of its liberal population. These political separations won't necessarily require civil war or even large-scale violence - Czechoslovakia peacefully divided into Slovakia and the Czech Republic after 74 years of political union - but in this case, it probably will due to the heavily ideological aspects of the divide.